The Impact of Neuronal and Neurotransmitter Abnormalities on Brain Function - Essay Example

? The impact of neuronal and neurotransmitter abnormalities on brain function Neuron as an integral part of CNS A huge amount of neurons and glia in human organism form our central nervous system (CNS), which is responsible for people’s mental abilities and their perception of surroundings. The most specific feature of neurons is that they able to transfer information from one cell to another within the whole human body by the instrumentality of electric impulses and chemical transmitters. Such system of information transportation is highly sensitive and delicate and in case there are any violations in neurons’ performance, serious brain disorders like Schizophrenia, Parkinson’s and Huntington’s diseases, Alzheimer’s, multiple sclerosis, and Down syndrome could develop. All of them are associated with decreasing patients’ intellectual abilities and certain physical abnormalities that affect significantly normal human activities (Deb S., McHugh R, 2010). Neurons are special nerve cells in human organism, which are able to transfer the information from one cell to another within the whole human body, and in such way support normal human activities and provide adequate reactions for all outside and inside irritants. According to Stufflebeam, “neurons are the basic information processing structures in the CNS” (Stufflebeam, 2008).  Neurons are joined in some kind of network with neuroglial cells that support and protect them providing all the conditions for transmitting electric impulses and special chemicals called transmitters. “Every information processing system in the CNS is composed of neurons and glia; so too are the networks that compose the systems (and the maps)…  Glia (or glial cells) are the cells that provide support to the neurons. ” (Stufflebeam, 2008).  There is a huge amount of different categories of neurons, which are quite diverse within their structure. Usually, the types of neuron cells are classified in the following way (Stufflebeam): sensory neurons serve for transmission of the information from sensory receptors to CNS by means nerve impulses though their long axons. Motor neurons are also equipped with comparably long axons and convey nerve impulses from CNS to muscles and glands in human body. Interneurons are also known as relay or connector neurons and commonly have cells of smaller size with a lot of interconnections to transfer information among different types of neurons. Neurotransmission process The main function of neuron cells is to receive the needful information from other neurons and to send it further through the whole human body. The process of information transferring is quite sophisticated and even nowadays there exist a lot of disagreements concerning its certain features. “Neurotransmission (or synaptic transmission) is communication between neurons as accomplished by the movement of chemicals or electrical signals across a synapse” (Stufflebeam, 2008).  There are two main stages in neuronal information transmitting (Stufflebeam): intracellular signaling represents communication between neurons through the instrumentality of special chemical mediums called neurotransmitters. intercellular signaling means that information is transmitted inside one neuronal cell in a form of electric impulses, which speed could reach 150 m/s. These impulses are called action potentials and are transferred through neurons’ axons. Further, they are transformed into transmitters at chemical synapses. According to Stufflebeam, “for any interneuron, its function is to receive INPUT "information" from other neurons through synapses, to process that information, then to send "information" as OUTPUT to other neurons through synapses” (Stufflebeam, 2008). Brain abnormalities Peter and Singer (2006) state that most of the brain’s cognitive functions are founded on the synchronized communications of many neurons, which leads to the obvious conclusion that even tiny deviations in normal neurons functioning could cause quite serious mental disorders like Schizophrenia, Parkinson’s and Huntington’s diseases, Alzheimer’s, multiple sclerosis, and Down syndrome. Treatment for all the abovedescribed mental diseases is not clearly defined and usually includes physiotherapy application, psychosocial and pharmaceutical interventions. Schizophrenia, Parkinson’s and Huntington’s diseases Schizophrenia is commonly accepted as a severe brain disorder, which is described with numerous psychotic indications like hallucinations and delusions, apathy, thoughts deregulations, memory and attention worsening, disorganization of thought and inadequate behavior in general (Peter & Singer, 2006). The main reason for schizophrenia is supposed to be various disruptions in neurons’’ ability to generate electric and chemical impulses, which significantly distorts patients’ perception of their surrounding (Deb S., McHugh R, 2010). According to Baker and Gershanik (2006), “Parkinson’s disease is a chronic progressive neurodegenerative disorder of insidious onset, characterized by the presence of predominantly motor symptomatology (bradykinesia, rest tremor, rigidity, and postural disturbances)” (Baker and Gershanik, 2006). Parkinson’s disease is usually associated with significant reduction dopamine-containing neurons, which is accompanied with postural instability, swallowing, speech and respiratory dysfunctions, etc. Gusella and MacDonald (2009) describe Huntington’s disease as a progressive neuronal disorder, which is activated by the mutations in certain chromosomes in human organism, which leads to neuronal cells death. As a consequence, patients who are affected Huntington’s disease, have gait instability while their mental abilities gradually decline. Alzheimer’s disease, multiple sclerosis and Down syndrome Tanzi and Bertram (2005) define Alzheimer’s disease as “a progressive neurodegenerative disorder characterized by global cognitive decline involving memory, orientation, judgment, and reasoning” (Tanzi and Bertram, 2005). They state that this kind of brain disorder is one of the most widespread mental illnesses, which is especially dangerous as there is no effective and proved method of treatment developed. “Alzheimer’s patients have lower levels of neurotransmitters, chemicals that carry complex messages back and forth between the nerve cells. For instance, Alzheimer’s disease seems to decrease the level of the neurotransmitter acetylcholine, which is known to influence memory” (Legendy, 2008). Another dangerous mental disorder is a multiple sclerosis, which is defined as ‘an in?ammatory demyelinating condition of CNS that is generally considered to be autoimmune in nature.’ (Douglas, Kesselring, Rompani, Singhal, and Thompson, 2006). Deviations from normal neurons functioning could occur at any location in CNS, which leads to a huge variety of accompanying symptoms, which include cognitive decline and even physical disability. Down syndrome, or trisomy, is the one of the most widespread causes of intellectual disability and brain disorders (Deb & McHugh, 2010). “In the normal brain, dendritic spines serve as connection points for synaptic transmission between the presynaptic axon terminal of one cell and the postsynaptic dendrite of the cell which is to receive the signal” (Harris, K.M., Stevens, J. K.,1989). Patients with Down syndrome have additional chromosome 21, which could be contained either in all their cells or only in a part of them. Similar to majority of other mental disorders, Down syndrome is supposed to affect people by chance; however, the children with mentally diseased parents are more likely to get trisomy. Summary A huge amount of neurons and glia in human organism build central nervous system of humans(CNS). This system is responsible for people’s mental abilities and their perception of surroundings. According to Kalat (2001), there are about 100 billion of neurons and 10 times more neuroglial cells in human organism, which are responsible for various functions and comprise together human central nervous system (CNS). The main role of neuron cells is to receive the necessary information from other neurons and to send it further through the whole human body. Neurons can transfer information from one cell to another within the whole human body by the instrumentality of electric impulses and chemical transmitters. The process of information transferring is quite sophisticated and even nowadays there exist a lot of disagreements concerning its certain features. The most specific feature of neurons is that they able to transfer information from one cell to another within the whole human body by the instrumentality of electric impulses and chemical transmitters. Such system of information transportation is highly sensitive and delicate and in case there are any violations in neurons’ performance, serious brain disorders. The most common mental diseases, which are associated with neurons deregulations, are Schizophrenia, Parkinson’s and Huntington’s diseases, Alzheimer’s, multiple sclerosis, and Down syndrome. Neurological diseases could be caused by some physical injuries of nerves, spinal cord or brain as well as the reason might be hidden in disbalance of human biochemical system. Due to the fact that the performance of neurons is not fully understood, it is often difficult to reveal the source problem and ascertain the disease at its early stage, which makes treatment for neurological disorders even more complicated. References 1. Baker M., Gershanik O. 2006 Parkinson’s disease. Neurological disorders: Public health challenges. World Health Organization report. Publication Year: 2006. 2. Deb S., McHugh R. 2010 Dementia among persons with Down syndrome. International Review of Research in Mental Retardation, 39, pp. 221-255. 3. Douglas I., Kesselring J., Rompani P., Singhal B., Thompson A. 2006 Multiple Sclerosis. Neurological disorders: Public health challenges. World Health Organization report. 4. Gusella J., MacDonald M. 2009 Encyclopedia of Neuroscience, pp. 35-37. [Online] Available at: http://www.sciencedirect.com/. [Accessed 25 February 2011]. 5. Harris, K.M., Stevens, J. K.1989 Journal of Neuroscience 9, 2982. 6. Legendy C. R. 2008 The new way to study brain signals. Columbia University 7. Peter U., Singer W. 2006 Neural synchrony in brain disorders: Relevance for cognitive dysfunctions and pathophysiology. Neuron journal, 52, pp. 155-168. 8. Tanzi R., Bertram L. 2005 Twenty years of the Alzheimer’s disease amyloid hypothesis: A genetic perspective. Cell journal, 120, pp. 545–555. 9. Stufflebeam R. 2008 Introduction to Neurons, Synapses, Action Potentials, and Neurotransmission.The Mind Project. National Science Foundation and National Institutes of Health. [Online] Available at: http://www.mind.ilstu.edu/. [Accessed 25 February 2011]. Read More